feat: add global MEV protection and refactor TradeConfig to builder pattern

- Add `mev_protection: bool` to `TradeConfig` and `InfrastructureConfig` (default: false)
  - Astralane QUIC: switches to port 9000 (MEV-protected endpoint) when enabled
  - BlockRazor HTTP: uses `mode=sandwichMitigation` query param when enabled
  - BlockRazor gRPC: uses `mode=sandwichMitigation` when enabled
- Add `SWQOS_ENDPOINTS_ASTRALANE_QUIC_MEV` constants (port 9000) to `constants/swqos.rs`
- Fix `astralane_quic.rs` IP candidates to use the actual port from the address (supports both 7000 and 9000)
- Refactor `TradeConfig` to builder pattern via `TradeConfig::builder()`
  - Introduce `TradeConfigBuilder` with all optional fields and clear defaults
  - `TradeConfig::new()` kept as a shortcut (calls `builder().build()`) for backward compatibility
  - Remove old `with_wsol_ata_config` / `with_check_min_tip` / `with_swqos_cores_from_end` / `with_mev_protection` chain methods
- Update all 16 examples to use `TradeConfig::builder()` with commented-out options so users can discover all available settings at a glance
- Update README.md and README_CN.md code snippets to use builder pattern

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sol-trade-sdk-nodejs/tsconfig.json

@@ -0,0 +1,29 @@
+{
+  "compilerOptions": {
+    "target": "ES2020",
+    "module": "commonjs",
+    "lib": ["ES2020"],
+    "declaration": true,
+    "strict": true,
+    "noImplicitAny": true,
+    "strictNullChecks": true,
+    "noImplicitThis": true,
+    "alwaysStrict": true,
+    "noUnusedLocals": false,
+    "noUnusedParameters": false,
+    "noImplicitReturns": true,
+    "noFallthroughCasesInSwitch": false,
+    "inlineSourceMap": true,
+    "inlineSources": true,
+    "experimentalDecorators": true,
+    "strictPropertyInitialization": false,
+    "outDir": "./dist",
+    "rootDir": "./src",
+    "skipLibCheck": true,
+    "esModuleInterop": true,
+    "resolveJsonModule": true,
+    "moduleResolution": "node"
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "dist"]
+}